Fuel delivery systems for direct injection and port injection applications, such as, for example, fuel-injected engines used in various types of on-road and off-road vehicles, typically include one or more fuel rails having a plurality of fuel injectors associated therewith. In such applications, the fuel rails include a plurality of outlet openings in which injector sockets or cups are affixed. The fuel injectors are inserted into and coupled with the injector cups so as to allow for the fuel flowing in the fuel rail to be communicated to the fuel injectors. The fuel communicated from the fuel rail to the fuel injectors is then communicated to the combustion chamber of the engine. Accordingly, in these arrangements the fuel injectors are sandwiched between the fuel rail and a corresponding cylinder head of the engine.
Conventional fuel injector cups generally take one of two forms. The first is normally used in low-pressure port fuel injection applications. This type of injector cup is typically stamped and includes a flange or ears that act as an attachment for retention clips that are used to retain the fuel injector within the fuel injector cup. The second is normally used in high-pressure direct injection applications. This type of injector cup is typically cast or forged and then subjected to secondary machining processes to create precise sealing surfaces for injector o-rings, as well as internal and/or external features for mating with the injector clip, for example.
Cast or forged cups, as opposed to stamped cups, are utilized in direct injection applications due to the force generated by the relatively high amount of pressure (i.e., on the order of 10-20 MPa or more) that is applied to the injector/injector clip/fuel injector cup interface in such systems. One drawback of cast/forged cups is that secondary machining processes or operations have to be performed on the cup to create the necessary surfaces and/or features required to allow for the sealing of the system and the retention of the injector within the cup. This secondary machining results in additional manufacturing steps, and therefore, complexity and cost, being added to the manufacturing process.
Therefore, there is a need for a fuel delivery system that will minimize and/or eliminate one or more of the above-identified deficiencies.